TY - JOUR
T1 - The major histocompatibility complex class II Ea promoter requires TFIID binding to an initiator sequence
AU - Bellorini, Marianna
AU - Dantonel, Jean Christophe
AU - Yoon, Jong Bok
AU - Roeder, Robert G.
AU - Tora, Laszlo
AU - Mantovani, Roderto
PY - 1996/2
Y1 - 1996/2
N2 - The major histocompatibility complex (MHC) class II Ea promoter is dependent on the presence of conserved upstream X and Y boxes and of initiator (Inr) sequences. In vitro transcription analysis of the Inr region with linker-scanning mutants pinpoints a functionally essential element that shows homology to the terminal deoxynucleotidyltransferase (TdT) Inr; contrary to the TdT Inr and other Inrs identified so far, the key sequence, between positions +5 and +12, is located within a transcribed area. Swapping the TdT sequence into the corresponding Ea position leads to a fivefold increase in transcription rate, without altering start site selection. Inr- binding proteins LBP-1/CP2 and TIP-a TdT Inr-binding protein unrelated to YY1-recognize the Ea Inr; they interact with overlapping yet distinct sequences around the Cap site, but their binding does not coincide with Ea Inr activity. A good correlation is, rather, found with binding of immunopurified holo-TFIID to this element. TFIID interacts both with Ea TATA- like and Inr sequences, but only the latter is functionally relevant. Unlike TBP, TFIID binds in the absence of TFIIA, indicating a stabilizing role for TBP-associated factors in Ea promoter recognition. Sequence comparison with other mouse and human MHC class II promoters suggests a common mechanism of start site(s) selection for the MHC class II gene family.
AB - The major histocompatibility complex (MHC) class II Ea promoter is dependent on the presence of conserved upstream X and Y boxes and of initiator (Inr) sequences. In vitro transcription analysis of the Inr region with linker-scanning mutants pinpoints a functionally essential element that shows homology to the terminal deoxynucleotidyltransferase (TdT) Inr; contrary to the TdT Inr and other Inrs identified so far, the key sequence, between positions +5 and +12, is located within a transcribed area. Swapping the TdT sequence into the corresponding Ea position leads to a fivefold increase in transcription rate, without altering start site selection. Inr- binding proteins LBP-1/CP2 and TIP-a TdT Inr-binding protein unrelated to YY1-recognize the Ea Inr; they interact with overlapping yet distinct sequences around the Cap site, but their binding does not coincide with Ea Inr activity. A good correlation is, rather, found with binding of immunopurified holo-TFIID to this element. TFIID interacts both with Ea TATA- like and Inr sequences, but only the latter is functionally relevant. Unlike TBP, TFIID binds in the absence of TFIIA, indicating a stabilizing role for TBP-associated factors in Ea promoter recognition. Sequence comparison with other mouse and human MHC class II promoters suggests a common mechanism of start site(s) selection for the MHC class II gene family.
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U2 - 10.1128/MCB.16.2.503
DO - 10.1128/MCB.16.2.503
M3 - Article
C2 - 8552077
AN - SCOPUS:0030053671
VL - 16
SP - 503
EP - 512
JO - Molecular and Cellular Biology
JF - Molecular and Cellular Biology
SN - 0270-7306
IS - 2
ER -